This disclosure relates generally to surgical devices and procedures, and more particularly, to orthopaedic surgical instruments.
During a typical surgical procedure for the internal fixation of a fractured bone, the orthopaedic surgeon attaches a metal bone plate to the bone with a number of bone fasteners, which may include screws, pegs, cables, and other types of fasteners. Before inserting the fastener, the surgeon must drill a properly sized hole at least partially into the bone, taking care to drill along a trajectory that allows good engagement of the fastener into the bone, avoids injury to adjacent soft tissues, and steers clear of other fasteners and structures.
The manufacturers of the many different bone plating systems currently available generally provide surgical drill guides for the surgeon to use with bone drill bits in order to drill the fastener holes. Some of these guides only can indicate the drill trajectory from the front, drill entry side of the bone. However, surgeons often need to visualize the exit location of a hole drilled through the bone to avoid injury to other tissues and structures on the back side of the bone. Other guides include proximal and distal structures for positioning on the front and back side of the bone, respectively, to indicate the entry and exit locations of the drilling trajectory, but these guides may include intricate mechanical components for adjusting the distance between the proximal and distal components. Some of these guides may be used for only one size drill bit so that it is necessary for the surgeon to switch guides when drilling a number of different diameter holes into the bone. Many guides require the surgeon to pass the drill bit tip through a guiding bore or channel of the guide prior to positioning the drill bit tip against the front side of the bone, such that the guide may not be removed from the surgical site until the drill bit is removed from the guide. In some situations, such guides may obstruct the surgeon's vision of important tissues and structures in the surgical site during drilling, when all the surgeons really need is to understand the drill trajectory through the bone for the initial portion of the drilling, after which point the drill bit normally follows along the same trajectory without the aid of the guide.